Various types of tests related to patient diagnosis and therapy can be performed by analysis of a sample of a patient's infection, bodily fluid or abscess for an analyte of interest. Patient samples are typically placed in closed sample tubes, the tubes transported to a clinical laboratory, placed into racks on an automated clinical analyzer and sample is extracted from the tubes. Subsequently, samples are combined in reaction vessels with various reagents extracted from reagent containers; the mixture is possibly incubated before being analyzed to aid in treatment of the patient. Interrogating measurements, turbidimetric or fluorometric or the like, are made to ascertain end-point or reaction rate values from which the amount of analyte in the sample may be determined, using well-known calibration techniques.
Automated clinical analyzers improve operating efficiency by providing results more rapidly while minimizing operator or technician error. Due to increasing demands on clinical laboratories regarding assay throughput, the efficiency of handling patient samples and reagents within an analyzer continually needs to be increased, and an important factor is the ability to maintain an adequate Inventory of reagents, quality control, and calibration solutions on-board and readily available such analyzers. Hereinafter, reagents, quality control, and calibration solutions may be referred to as standard chemical solutions.
The sample rack is usually placed by an operator in an input portion of the analyzer and automatically moved by the analyzer to an aliquotting location where an aliquot of the liquid patient sample is extracted, usually by aspiration using a hollow probe from the sample container. Aliquot samples from a number of different patient samples may be dispensed into a plurality of interim vessels or wells formed as an integral array of small open cup-like vessels, herein called an aliquot vessel array, like that described in U.S. patent Ser. No. 10/037,512, assigned to the assignee of the present invention. Aliquot vessel arrays are transported to a sampling location where an appropriate amount of the aliquot sample is extracted by a sampling probe and dispensed by a sampling probe into a reaction cuvette. In addition, standard chemical solutions required to conduct specified assays are extracted at a reagenting location from appropriate assay chemical containers or containers using hollow probes that are subsequently shuttled to assay chemical solution dispensing locations where standard chemical solutions are dispensed into the reaction cuvette.